JPS60222747A - Method for testing roll angular corugation forming processability of film on coated metal plate - Google Patents

Abstract

PURPOSE:To make it possible to quantitatively grasp the scratch generation degree on the film when the roll angular corugation forming is subjected to processing, by bringing a rotary metal wheel different in a peripheral speed into tangental contact with one point of the film surface on a metal plate during rotation so as to apply required load thereto. CONSTITUTION:The test piece 3 of a coated metal plate is placed on and fixed to the turntable 2 rotated by a motor 1 so as to upwardly direct the film surface 3a thereof. The chromium plated metal wheel 6 rotated by a motor 5 so as to provided required peripheral speed difference from the rotary peripheral speed of the test piece 3 is brought into tangential contact with one point on the rotary circumference of the film surface 3a so as to apply press load W thereto. The damage degree in the film surface 3a, when the turntable 2 is rotated in said state predetermined times, is inspected to test the roll square wave forming processability of the film. By this method, the scratch generation degree can be quantitatively and well grasped even to a small test piece.

Description

[Detailed description of the invention] Concerning wave forming processability test method.

Whether or not scratches occur on the coating surface when a coated metal plate is subjected to roll square wave forming is related to the hardness and slipperiness of the coating.

Common test methods for coating film hardness include pencil hardness test,
There are coin scratch tests, drawing tests, taper set abrasion tests, etc., but in terms of the correlation between these test results and the occurrence of scratches on the coating film during actual roll square wave forming processing,
There are some cases in which a proportional relationship does not hold, and the reliability is not sufficient.

Furthermore, with these test methods, it is not possible to routinely determine whether the degree of scratches is good or bad.

Therefore, during the roll square wave forming process of painted metal plates,
The reality is that tests are being conducted.

In testing the formability of the coating film using this practical roll forming machine or a small test roll forming machine, a plate 1111ii with a length of at least 80 cm that can be passed through the roll forming machine and formed. A coated metal plate with a size of 30 cm for testing is required, and painting equipment and baking equipment are required to create the coated metal plate for testing. It takes a lot of time and effort to conduct the test, such as adjusting the roll clearance by matching the thickness. Conventionally, the test can be performed extremely easily using a small test piece, and it is also possible to check whether the scratches are good or not. There was a desire for a test method that could be used to determine static electricity.

The present invention was developed to meet such demands, and an example of its implementation will be described below.

The figure is an explanatory diagram showing an outline of the method of the present invention, in which a test piece 3 of a painted metal plate is placed and fixed on a turntable 2 rotated by a motor 1 with its coated surface 3a facing upward.

The test piece 3 can be fixed on the turntable 2 by drilling a hole in the center of the test piece 3, aligning this hole with the female threaded hole at the center of the turntable 2, and fixing the test piece 3 with a set bolt 4.

Then, at one point on the rotational circumference of the coating surface 3a of the test piece 3 placed and fixed on the turntable 2, a chrome plate is rotated by the motor 5 at a rotational peripheral speed of the test piece 3 and a required peripheral speed difference. The plated metal wheels 6 are brought into tangential contact by applying a rolling load W by any means.

As the means for applying the rolling load NW, for example, a rolling load means using a spring, a rolling load means similar to the rolling means of a rolling roll, etc. may be used.

Therefore, on the turntable 2, the coating film adhesion method 229/
A test piece 3 of a painted metal plate with an area of 10 cm square is mounted and fixed with the coating surface 3a facing upward, and the metal wheel 6 is placed on the coating film of the test piece 3 at a position 4 cm from the center of the turntable 2. Test piece 3 when applying a rolling load of 500 g to a point on the rotational circumference of surface 3a and making tangential contact with it, rotating this tangent-pull 2 and metal wheel 6, and rotating turntable 2 100 times. The degree of damage on the coating surface 3a was examined.

Two types of test pieces 3, A and B, were prepared and tested under the same conditions.

A is polyester tochi resin paint manufactured by Nippon Oil & Fats Co., Ltd. (
Product number #3720) is a test piece that has a coating surface with an anti-glossy agent added to prevent uneven gloss of the paint film when baked. This is a test piece with a coating surface.

In addition, in order to compare with the test method according to the present invention described above, test specimens A and B or test coated metal plates A having a length of 80 ctn and a width of 30 cm were prepared under exactly the same conditions as test specimens A and B. ,B respectively, pencil hardness test,
Pheasant roll rubbing test, folding test, drawing test,
Rock forming test, rib corrugation processing test, nine-wave processing test, deep drawing test, impact press test, coin scratch test, taper set wear test, roll square wave forming processing test were conducted, and the coating film was determined by the test method of the present invention. The degree of damage to the surface,
The degree of damage to the paint film surface by each test method was compared.

The comparison results are shown in Table 1 below.

In Table 1 below, the test pieces and the test coated metal plates are collectively referred to as samples.

(Left below) Table 1 As is clear from Table 1 above, there is a correlation between the degree of damage to the paint film surface by the test method of the present invention and the degree of damage to the paint film surface by the roll corner wave forming process. This means that the test method of the present invention reproduces the degree of damage to the coating film surface during the square wave forming process in actual operation.

Therefore, for example, the relative circumferential speed ratio and the rolling load W at the tangential contact point of the metal mold ring 6 with respect to the turntable 2.
By comparing the degree of damage to each coating surface when the number of rotations of the turntable 2 is varied while holding constant , the degree of damage to the coating surface during actual roll angle wave forming processing can be quantitatively determined in advance. You can understand it.

Note that the relative circumferential speed ratio at the tangential contact point between the turntable 2 and the metal ring 6 is suitably 1.0:0.8 to 0.9.

As described above, according to the method of the present invention, the roll angular wave forming processability of a coating film on a painted metal plate can be very clearly tested in the laboratory using small test pieces, and the roll angular wave forming process in actual operation can be Since the degree of damage to the coating surface during processing can be quantitatively grasped in advance, it can significantly contribute to improving the workability of roll square wave forming of coated metal sheets.

[Brief explanation of drawings]

The figure is an explanatory diagram showing an outline of the method of the present invention.

Claims (1)

[Claims] A test piece of a painted metal plate is rotated at a constant speed, and a metal leg shaft that rotates at a point on the rotational circumference of the coating film ml of this test piece with a difference between the rotational peripheral speed of the test piece and the required peripheral speed, A test method for roll angle wave forming of a coating film on a painted metal plate, which is characterized by applying a required rolling load and bringing the film into tangential contact.